This paper will discuss the state of the existing 1950's vintage engine compressor units prior to the upgrade and will further show the specific upgrades which were made thereafter. The presentation will delineate what specific technologies were replaced or upgraded in an effort to improve reliability and protection of the engines and compressors, which are controlled to operate from a remote location. The presentation will specifically discuss what old-style technologies were replaced, upgraded or left as is, including communication technologies for remote control. Successful approaches, as well as lessons-learned will be discussed.